Deficit di micronutrienti e metabolismo osseo nella celiachia e nelle malattie infiammatorie croniche intestinali.

Inadequate dietary intake of Vitamin D, Vitamin K and calcium as well as inadequate sunlight exposure favor bone loss in the general population, more so in inflammatory bowel disease (IBD) and celiac disease. In these diseases other risk factors are present, including inflammation, but dietary factors, if present, are easily corrected. While the relation between calcium and Vitamin D, and bone metabolism are well known, less data is available for Vitamin K both in healthy individuals and patients. Aim of the study was to evaluate a wide set of bone metabolism markers, bone specific alkaline phosphatase (BALP), carboxylated and undercarboxylated osteocalcin (ucOC), procollagen type I N-terminal propeptide (PINP), tartrate resistant acid phosphatase (TRAcP), serum type I collagen cross-linked C-telopeptide (CTX), in IBD-, celiac patients and controls, correlating these findings with blood levels of vitamin D and K, and their nutritional intake. A 28-item quantitative food frequency questionnaire and a 12-item sunlight exposure questionnaire were administered to 111 IBD patients (58 Crohn’s disease and 53 ulcerative colitis), 61 patients with celiac disease and 112 controls. Patients’ demographics, clinical, endoscopic and laboratory findings were analyzed in relation to recommended daily allowances (RDA). Bone mineral density was assessed by densitometry. PINP, a marker of osteoblastic activity, was significantly higher in IBD patients compared to controls (9.16±8.84 vs. 7.60±8.84 ng/ml, p=0.0005). No difference was detected for BALP, TRAcP, and CTX. Age influenced the levels of BALP and TRAcP in females and values were significantly higher in older subjects, both in IBD and controls compared to younger age groups. High levels of CTX were present In IBD patients with active disease vs. inactive disease. No other marker was influenced by disease activity. With regard to vitamin K intake markers, ucOC levels were non-significantly lower in IBD patients versus controls (p=0.07). A trend toward higher concentrations in Crohn’s disease compared to ulcerative colitis was also observed. Significantly higher concentrations of ucOC were present in male (p= 0.02) both in IBD and controls, likely due to a lower intake of green leafy vegetables compared to women. The mean Vitamin K intake calculated on the base of questionnaires was less than adequate in IBD and normal in controls (IBD 59.56% RDA vs. controls 107.15% RDA, p < 0.0001). A significant difference in vitamin K levels was detected also between celiac patients and controls, but was less pronounced than in IBD (celiac disease 98.78% vs. controls 107.15%; p = 0.0001; celiac disease 98.78% vs. IBD 59.56%, p < 0.0001). The vitamin D intake was inadequate in IBD, celiac and control patients (55.29% RDA, 60.47% RDA, and 65.34% RDA, respectively), resulting in the absence of statistically significant differences between controls and patient groups. No significant correlation was found between blood vitamin D levels and sunlight exposure In IBD and celiac patients, as well as in relation to the season of blood sampling. Conversely, as expected, the levels of vitamin D in controls were significantly lower in winter than in summertime (IBD 17.41 vs. 17.15 mg/dl, p= 0.81; controls 21.35 vs 26.93 mg/dl, p< 0.05). No difference in vitamin D concentration was reported In IBD in relation to disease activity indexes as creactive protein, fecal calprotectin, clinical or endoscopic disease activity. Calcium intake was non-significantly lower in IBD and celiac disease patients compared to controls (IBD 100.17% RDA, celiac disease 102.45%, controls 107.15%). Bone densitometry showed osteopenia in 27/63 IBD patients (42.86%) and 14/23 celiac patients (60.87%), and osteoporosis in 13/63 IBD (20.64%) and 4/23 celiacs (17.39%). These